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In one embodiment of the invention, a method of automatically balancing
ionized air stream created in bipolar corona discharge is provided. The
method comprises: providing an air moving device with at least one ion
emitter and reference electrode connected to a micro-pulsed AC power
source, and a control system with at least one ion balance monitor and
corona discharge adjustment control; generating variable polarity groups
of short duration ionizing micro-pulses: wherein said micro-pulses are
predominantly asymmetric in amplitude and duration of both polarity
voltages and have a magnitude of at least one polarity ionizing pulses
exceed the corona threshold.

1. An apparatus for an automatically balanced ionizing blower,
comprising: an ion balance control system configured to sample and
compare output signals from at least one of a remote ionization current
return sensor or a remote ionization voltage sensor in a time interval
between ionizing pulses.

2. The apparatus of claim 1, wherein the ion balance control system is
configured to receive the output signals from the at least one of the
remote ionization current return sensor or the remote ionization voltage
sensor via a wired connection.

3. The apparatus of claim 1, wherein the ion balance control system is
configured to receive the output signals from the at least one of the
remote ionization current return sensor or the remote ionization voltage
sensor via a wireless connection.

4. The apparatus of claim 3, wherein the ion balance control system and
the at least one of the remote ionization current return sensor or the
remote ionization voltage sensor are individually addressable via the
wireless connection.

5. The apparatus of claim 3, wherein the ion balance control system is
configured to be paired to the at least one of the remote ionization
current return sensor or the remote ionization voltage sensor to receive
the output signals.

6. The apparatus of claim 1, wherein the ion balance control system is
further configured to compare the output signals from the remote
ionization current return sensor and the remote ionization voltage
sensor.

7. A control system of a balanced micro-pulsed ionizing blower, the
control system comprising: a micro-pulsed high voltage AC (alternating
current) power source configured to generate short duration positive
polarity ionizing pulses and short duration negative polarity ionizing
pulses; an ion balance control system configured to receive output
signals from at least one of a remote ionization current return sensor or
a remote ionization voltage sensor in a time interval between the
ionizing pulses; and a microcontroller configured to control the AC power
source based on the output signals.

8. The control system of claim 7, wherein the ion balance control system
is configured to receive the output signals from the at least one of the
remote ionization current return sensor or the remote ionization voltage
sensor via a wired connection.

9. The control system of claim 7, wherein the ion balance control system
is configured to receive the output signals from the at least one of the
remote ionization current return sensor or the remote ionization voltage
sensor via a wireless connection.

10. The control system of claim 9, wherein the ion balance control system
and the at least one of the remote ionization current return sensor or
the remote ionization voltage sensor are individually addressable via the
wireless connection.

11. The control system of claim 9, wherein the ion balance control system
is configured to be paired to the at least one of the remote ionization
current return sensor or the remote ionization voltage sensor to receive
the output signals.

12. The control system of claim 7, wherein the ion balance control system
is further configured to compare the output signals from the remote
ionization current return sensor and the remote ionization voltage
sensor.

13. The control system of claim 7, wherein the microcontroller achieves
an ion balance by at least one of: increasing and/or decreasing a
positive pulse width value and/or negative pulse width value of the
ionizing pulses; increasing and/or decreasing a time between positive
pulses and/or negative pulses of the ionizing pulses; or increasing
and/or decreasing a number of positive polarity pulses and/or negative
polarity pulses of the ionizing pulses.

14. A method of providing control in a balanced micro-pulsed ionizing
blower, the method comprising: generating short duration positive
polarity ionizing pulses and short duration negative polarity ionizing
pulses; wherein generating the ionizing pulses further comprises:
receiving output signals from at least one of a remote ionization current
return sensor or a remote ionization voltage sensor in a time interval
between the ionizing pulses; and controlling an AC power source for
generating the ionizing pulses based on the output signals.

15. The method of claim 14, wherein the receiving the output signals from
the at least one of the remote ionization current return sensor or the
remote ionization voltage sensor comprises receiving the output signals
via a wired connection.

16. The method of claim 14, wherein the receiving the output signals the
output signals from the at least one of the remote ionization current
return sensor or the remote ionization voltage sensor comprises receiving
the output signals via a wireless connection.

17. The method of claim 16, wherein the at least one of the remote
ionization current return sensor or the remote ionization voltage sensor
are individually addressable via the wireless connection.

18. The method of claim 16, further comprising establishing pairing with
the at least one of the remote ionization current return sensor or the
remote ionization voltage sensor to receive the output signals.

19. The method of claim 14, further comprising comparing the output
signals from the remote ionization current return sensor and the remote
ionization voltage sensor.

20. The method of claim 14, further comprising achieving an ion balance
based on controlling at least one of the following: increasing and/or
decreasing a positive pulse width value and/or negative pulse width value
of the ionizing pulses; increasing and/or decreasing a time between
positive pulses and/or negative pulses of the ionizing pulses; or
increasing and/or decreasing a number of positive polarity pulses and/or
negative polarity pulses of the ionizing pulses.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation-in-part of U.S. application Ser.
No. 14/711,611, filed May 13, 2015, which is a continuation of U.S.
application Ser. No. 14/220,130, filed Mar. 19, 2014, which is a
continuation-in-part of U.S. application Ser. No. 13/367,369, filed Feb.
6, 2012. The entireties of U.S. patent application Ser. No. 13/367,369,
U.S. patent application Ser. No. 14/220,130, and U.S. patent application
Ser. No. 14/711,611 are incorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Technical Field

[0003] Embodiments of the invention generally relate to ionizing blowers.

[0004] 2. Background Art

[0005] Static charge neutralizers are designed to remove or minimize
static charge accumulation. Static charge neutralizers remove static
charge by generating air ions and delivering those ions to a charged
target.

[0006] One specific category of static charge neutralizers is the ionizing
blower. An ionizing blower normally generates air ions with a corona
electrode, and uses a fan (or fans) to direct air ions toward the target
of interest.

[0007] Monitoring or controlling the performance of a blower utilizes two
measurements.

[0008] The first measurement is balance. Ideal balance occurs when the
number of positive air ions equals the number of negative air ions. On a
charge plate monitor, the ideal reading is zero. In practice, the static
neutralizer is controlled within a small range around zero. For example,
a static neutralizer's balance might be specified as approximately
.+-.0.2 volts.

[0009] The second measurement is air ion current. Higher air ion currents
are useful because static charges can be discharged in a shorter time
period. Higher air ion currents correlate with low discharge times that
are measured with a charge plate monitor.

BRIEF SUMMARY

[0010] In an embodiment of the invention, a method of automatically
balancing ionized air stream created in bipolar corona discharge is
provided. The method comprises: providing an air moving device with at
least one ion emitter and reference electrode connected to a micro-pulsed
AC power source, and a control system with at least one ion balance
monitor and corona discharge adjustment control; generating variable
polarity groups of short duration ionizing micro-pulses: wherein said
micro-pulses are predominantly asymmetric in amplitude and duration of
both polarity voltages and have a magnitude of at least one polarity
ionizing pulses exceed the corona threshold.

[0011] In another embodiment of the invention, an apparatus for an
automatically balanced ionizing blower is provided. The apparatus
comprises: an air moving device and at least one ion emitter and
reference electrode both connected to a high voltage source; and an ion
balance monitor; wherein a transformer of said high voltage source, said
ion emitter and reference electrode arranged in a closed loop for AC
current circuit and said loop connected to ground by a high value viewing
resistor.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Various embodiments of this disclosure that are proposed as
examples will be described in detail with reference to the following
figures, wherein like numerals reference like elements, and wherein:

[0013] FIG. 1A is a block diagram of a general view of an ionizing blower,
in accordance with an embodiment of the invention.

[0014] FIG. 1B is a cross sectional view of the blower of FIG. 1A.

[0015] FIG. 1C is a block diagram of a sensor included in an ionizing
blower, in accordance with an embodiment of the invention.

[0016] FIG. 2A is a block diagram of the ionizing blower of FIG. 1A and
the ionized air stream from the blower, in accordance with an embodiment
of the invention.

[0017] FIG. 2B is an electrical block diagram of a system in the ionizing
blower, in accordance with an embodiment of the invention.

[0018] FIG. 3 is a flowchart of a feedback algorithm 300, in accordance
with an embodiment of the invention.

[0019] FIG. 4 is a flowchart of a micropulse generator algorithm of a
micropulse generator control, in accordance with an embodiment of the
invention.

[0020] FIG. 5A is a flowchart of a system operation during the formation
of a negative pulse train, in accordance with an embodiment of the
invention.

[0021] FIG. 5B is a flowchart of a system operation during the formation
of a positive pulse train, in accordance with an embodiment of the
invention.

[0022] FIG. 6 is a flowchart of a system operation during a present pulse
phase, in accordance with an embodiment of the invention.

[0023] FIG. 7 is a flowchart of a system operation during the sensor input
measurement, in accordance with an embodiment of the invention.

[0024] FIG. 8 are waveform diagrams of micropulses, in accordance with an
embodiment of the invention.

[0025] FIG. 9 is a flowchart of a system operation during a balance alarm,
in accordance with an embodiment of the invention.

DETAILED DESCRIPTION

[0026] In the following detailed description, for purposes of explanation,
numerous specific details are set forth to provide a thorough
understanding of the various embodiments of the present invention. Those
of ordinary skill in the art will realize that these various embodiments
of the present invention are illustrative only and are not intended to be
limiting in any way. Other embodiments of the present invention will
readily suggest themselves to such skilled persons having benefit of the
herein disclosure.

[0027] An embodiment of the present invention can apply to many types of
air-gas ionizers configured as, for example, ionizing bars, blowers, or
in-line ionization devices.

[0028] Wide area coverage ionizing blowers requires combination of highly
efficient air ionization with short discharge time and tight ion balance
control. FIG. 1A is a block diagram of a general view of an ionizing
blower 100, in accordance with an embodiment of the invention, while FIG.
1B is a cross sectional view of the blower 100 of FIG. 1A along the line
A-A. The efficient air ionization is achieved by the bipolar corona
discharge created between the array of emitter points 102 (i.e., emitter
points array 102) and two reference electrodes 104,105 (shown as upper
reference electrode 104 and lower reference electrode 105). The emitter
points 102 mounted on a protective grill 106 (i.e., air duct 106) which
also helps equally to speed an ionized air flow.

[0029] A fan 103 (FIG. 1A) is an air moving device that provides a high
variable air flow 125 in a space 130 between the emitter points array 102
(ion emitter(s) 102) and the two reference electrodes 104,105. The air
duct 106 concentrates and distributes air flow 125 in the space 130 of a
corona discharge. Corona generated positive and negative ions are moving
between electrodes 102, 104 and 105. The air flow 125 is able to take and
carry only a relatively small portion of positive and negative ions
created by the corona discharge.

[0030] According to one embodiment of the invention, the air 125 is forced
out of the air duct (106) outlet 131 and the air 125 passes an air
ionization sensor 101. Details one embodiment of a design of the sensor
101 are shown in FIG. 1C. A fan (shown as block 126 in FIG. 1B) provides
the flow of air 125. The air ionization voltage sensor 101 has a louver
type thin dielectric plate 109 stretched on full width of the duct 106.
The louver plate 109 directs a portion 125a (or sample 125a) of the
ionized air flow 125b (ionized air stream 125b) coming from the duct 106
and upper electrode 104 (see also FIG. 2A), so that the sensor 101 can
sense and collect some of the ion charges in the portion 125a of the
ionized air flow 125b. The collected ion charges then creates the control
Signal 250 (FIG. 2) for use by the algorithm 300 (FIG. 3) for balancing
the ions in the ionizing blower 100. A top side 132 of the plate 109 has
a narrow metal strip functioning as a sensitive electrode 108 and a
bottom side 133 has wider grounded plain electrode 110. This electrode
110 is typically shielded so that the air ionization sensor 101 is
shielded from the high electrical field of the emitter points array 102.
The electrode 108 collects some of the ion's charges resulting in a
voltage/signal 135 (FIG. 2A) that is proportional to ion balance in the
ionized air flow 125b. The voltage/signal 135 from sensor 101 used by the
control system 107 (shown in FIG. 2 as system 200) to monitor and adjust
the ion balance in the ionized air flow 125b. This signal 135 is also
represented by the signal 250 which is input into the sample and hold
circuit 205 as will be discussed further below. Other configurations of
ion balance sensors, for example, in the form of conductive grille or
metal mesh immersed in the ion flow also can be used in other embodiments
of the invention.

[0031] According to another embodiment of the invention, an ion current
sensor 204 is used to monitor ionized flow balance. Therefore, one
embodiment of the invention provides a system 200 (FIG. 2) comprising the
ionization return current sensor 204 for monitoring the ionized air flow
balance. In another embodiment of the invention, the system 200 comprises
the air ionization voltage sensor 101 for monitoring the ionized air flow
balance.

[0032] In yet another embodiment of the invention, the system 200
comprises the dual sensors comprising the air ionization voltage sensor
101 and ionization current return sensor 204, with both sensors 101 and
204 configured for monitoring the ionized air flow balance.

[0033] In some examples, the ionization voltage sensor 101 and/or the
ionization current return sensor 204 are remote sensor(s) directly wired
to the control system 107. In some other examples, the ionization voltage
sensor 101 and/or the ionization current return sensor 204 are
implemented as remote wireless sensor(s) with radio frequency (RF)
communication, Bluetooth, and/or any other wireless method for
communication. A remote sensor refers to the sensor being external to the
ionizing blower 100. The example ionizing blower 100 may receive active
(e.g., powered) and/or passive (e.g., non-powered) feedback signal(s)
from wired and/or wireless remote ionization voltage sensors 101 and/or
ionization current return sensors 204 at the control system 107 of the
ionizing blower 100.

[0034] Because the ionizing blower 100 may be used in applications or
environments in which multiple, or even large numbers (e.g., tens,
hundreds, or more) of ionizing blowers 100 and wireless ionization
voltage sensors 101 and/or ionization current return sensors 204 are used
within the wireless communication range of the ionization voltage sensors
101 and/or ionization current return sensors 204, in some examples the
ionization voltage sensors 101 and/or ionization current return sensors
204 are individually addressable and have unique identifiers to enable
specific pairing of sensors 101, 204 to individual ionizing blowers 100.

[0035] In examples in which the ionization voltage sensor 101 and/or the
ionization current return sensor 204 are remote sensor(s), the example
control system 107 includes a communications circuit to receive the wired
and/or wireless communications from the ionization voltage sensor 101
and/or the ionization current return sensor 204.

[0036] The ionization return current sensor 204 includes the capacitor C2
and capacitor C1, and resistors R1 and R2. The capacitor C2 provides an
AC current path to ground, bypassing the current detect circuit. The
resistor R2 converts the Ion current to a voltage (Ii*R2), and the
resistors R1 and R2 and capacitor C2 form a low pass filter to filter out
induced currents created by the micro pulse. The return current 210
flowing from the sensor 204 is shown as 12.

[0037] The current 254 flowing to the emitter points 102 is the current
summation .SIGMA.(Ii(+),Ii(-),I2,Ic1,Ic2) where the currents Ic1 and Ic2
are the currents flowing through the capacitors C1 and C2, respectively.

[0038] FIG. 2A illustrates ion currents 220 flowing between the emitters
102 and reference electrodes 104, 105. The air flow 125 from the duct 106
converts a portion of these two ion currents 220 in an ionized air flow
125b which is moving to a target of charge neutralization outside the
blower 100. The target is generally shown in FIG. 1B as the block 127
which can be placed in different locations with respect to the ionizing
blower 100.

[0039] FIG. 2B shows an electrical block diagram of a system 200 in the
ionizing blower 100, in accordance with an embodiment of the invention.
The system 200 includes an Ion current sensor 204, micro-pulse high
voltage power supply 230 (micro-pulsed AC power source 230) (which is
formed by the pulse driver 202 and high voltage (HV) transformer 203),
and a control system 201 of the Ionizing blower. In an embodiment, the
control system 201 is a microcontroller 201. The microcontroller 201
receives a power from a voltage bias 256 which may be at, for example,
about 3.3 DC voltage and is grounded at line 257.

[0040] A power converter 209 may be optionally used in the system 200 to
provide various voltages (e.g. -12 VDC, 12 VDC, or 3.3 VDC) that is used
by the system 200. The power converter 209 may convert a voltage source
value 258 (e.g., 24 VDC) into various voltages 256 for biasing the
microcontroller 201.

[0041] The micro-pulse high voltage power supply 230 has a pulse driver
202 controlled by Micro-Controller 201. The pulse driver 202 is connected
to a step up pulse transformer 203. The transformer 203 generates short
duration pulses (in microsecond range) positive and negative polarities
having amplitudes sufficient to produce corona discharge. The secondary
coil of the transformer 203 is floated relatively to ground. A high
voltage terminal 250 of transformer 203 is connected to the emitter
points array 102 and a low voltage terminal 251 of transformer 203 is
connected to the reference electrodes 104, 105.

[0042] The short duration high voltage AC pulses (generated by the high
voltage power supply 230) result in significant capacitive or
displacement currents Ic1 and Ic2 flowing between electrodes 102 and
104,105. For example, the current Ic1 flows between the electrodes
(emitter points) 102 and the upper reference electrode 104, and the
current Ic2 flows between the electrodes 102 and the lower reference
electrode 105. Relatively small positive and negative ion corona currents
marked as Ii(+) and Ii(-) leave this ions generation system 200 into the
environment outside blower 100 and moving to the target.

[0043] To separate the capacitive and ion currents, the ion generating
system 200 is arranged in a closed loop circuit for high frequency AC
capacitive currents marked Ic1 and Ic2 as the secondary coil of
transformer 203 and corona electrodes 102,104 and 105 are virtually
floated relative to ground and the ion currents Ii(+) and Ii(-) have a
return path (and transmits) to ground. AC currents have significantly
lower resistance to circulate inside this loop than these AC currents
transmitting to ground.

[0045] Additionally, ion balance monitoring is performed in the system 200
during time periods between the micro-pulses. Additionally, ion balance
monitoring is performed by integrating differential signals of the
positive and negative convection currents.

[0046] The transformer 203 of the high voltage source 230, the ion emitter
102 and reference electrode 104 or 105 are arranged in a closed loop for
AC current circuit and the closed loop is connected to ground by a high
value viewing resistor R2.

[0047] The law of charge conservation dictates that as the output (via
transformer 203) of AC voltage source 230 is floated, the ion current is
equal to a sum of positive Ii(+) and negative Ii(-) ion currents. These
currents Ii(+) and Ii(-) have to return through the circuitry of the
return current sensor 204 in the system 200. The amount of each polarity
ion current are:

Ii(+)=Q(+)*N(+)*U and Ii(-)=Q(-)*N(-).*U

[0048] Where Q is charge of positive or negative ion, N is ion
concentration, and U is air flow. An ion balance will be achieved if
absolute values of positive Ii(+) and negative Ii(-) currents are the
same. It is known in the art that both polarities of air ions carry about
the same amount of charge (equal to one electron). So, another condition
of ion balance is equal concentrations of both polarity ions. The air
ionization voltage sensor 101 (ion balance monitor 101) is more sensitive
to variation in the ion concentration, in contrast to the return current
sensor 204 (ion balance monitor 204) which is sensitive to ion currents
changes. Therefore, the speed of the response of the air ionization
voltage sensor (capacitor sensor) 101 is typically faster than the
response of the ionization return current sensor 204.

[0049] A greater number of positive ions detected by the sensor 101
results in the sensor 101 generating a positive output voltage that is
input into (and processed by) the sample and hold circuit 205. A greater
number of negative ions detected by the sensor 101 results in the sensor
101 generating a negative output voltage that is input into (and
processed by) the sample and hold circuit 205. In contrast, as similarly
described above, absolute values of positive Ii(+) and negative Ii(-) are
used by the sensor 204 to output the signal 250 for input into the sample
and hold circuit 205 to determine and achieve an ion balance in the
ionization blower 100.

[0050] At the time between a micropulse train, the sample signal 215 will
close the switch 216 so that amplifier 218 is connected to the capacitor
C3 which is then charged to a value based in response to the input signal
250.

[0051] The ion currents floated with air stream are characterized by very
low frequency and can be monitored by passing through a high mega ohm
resistive circuitry R1 and R2 to ground. To minimize the influence of
capacitive and parasitic high frequency currents, the sensor 204 has two
bypass capacitive paths with C1 and C2.

[0052] The difference in currents Ii(+) and Ii(-) are continuously
measured by sensor 204. The resulting current passing though resistive
circuitry R1, R2 produces a voltage/signal proportional to
integrated/averaged in time ion balance of the air stream that left the
blower. This resulting current is shown as current 214 which is expressed
by the summation .SIGMA.(Ii(+),Ii(-)).

[0053] The ion balance monitoring is achieved by measuring voltage output
of current sensor 204, or by measuring output of voltage sensor 101, or
by measuring voltage from an air ionization sensor 101 and 204. For
purposes of clarity, the voltage outputs of the current sensor 204 and
voltage output of voltage sensor 101 are each shown in FIG. 2 by the same
signal 250. This signal 250 is applied to the input of a sample and hold
circuit 205 (sampling circuit 205) that is controlled by the
Microcontroller 201 via the sample signal 215 which opens the switch 216
to trigger a sample and hold operation on the signal 250.

[0054] In some cases or embodiments for corona system, diagnostic signals
from both sensors 101 and 204 can be compared. These diagnostic signals
are input as signal 250 into the sample and hold circuit 205.

[0055] The signal 250 is then conditioned by a low pass filter 206 and
amplified by the amplifier 207 before being applied to the input of the
Analog to Digital Converter (ADC) residing inside the Microcontroller
201. The sample and hold circuit 205 samples the signal 250 between
pulses times to minimize noise in the recovered signal 250. Capacitor C3
holds the last signal value in-between sample times. Amplifier 207
amplifies the signal 250 to a more usable level for the microcontroller
201, and this amplified signal from the amplifier 207 is shown as the
balance signal 252.

[0056] The microcontroller 201 compares the balance signal 252 with a
setpoint signal 253 which is a reference signal generated by the balance
adjustment potentiometer 208. The setpoint signal 253 is a variable
signal that can be adjusted by the potentiometer 208.

[0057] The setpoint signal 253 can be adjusted in order to compensate for
different environments of the ionizing blower 100. For example, the
reference level (ground) near the output 131 (FIG. 1B) of the ionizing
blower 100 may be approximately zero, while the reference level near an
ionization target may not be zero. For example, more negative ions might
be lost at the location of the ionization target if the location has a
strong ground potential value. Therefore, the setpoint signal 253 may be
adjusted so as to compensate for the non-zero value of the reference
level at a location of the ionization target. The setpoint signal 253 can
be decreased in this case so that the microcontroller 201 can drive the
pulse driver 202 to control the HV transformer 230 to generate an HV
output 254 that generates more positive ions at the emitter points 102
(due to the lower setpoint value 253 used as a comparison for trigger
more positive ions generation) so as to compensate for the loss of
negative ions at the location of the ionization target.

[0058] Reference is now made to FIGS. 2 and 8. In an embodiment of the
invention, the ionization blower 100 can achieve an ion balance in the
ionizing blower 100 based on at least one or more of the following: (1)
by increasing and/or decreasing the positive pulse width value and/or
negative pulse width value, (2) by increasing and/or decreasing the time
between positive pulses and/or time between negative pulses, and/or (3)
by increasing and/or decreasing the number positive pulses and/or
negative pulses, as described below. The microcontroller 201 outputs the
positive pulse output 815 and negative pulse output 816 (FIGS. 2 and 8)
which are driven into and controls the pulse driver 202. In response to
the outputs 815 and 816, the transformer 230 generates the ionization
waveform 814 (HV output 814) that is applied to the emitter points 102 so
as to generate an amount of positive ions and an amount of negative ions
based on the ionization waveform 814.

[0059] As an example, if the sensor 101 and/or sensor 204 detects an ion
imbalance in the ionizing blower 100 where the amount positive ions
exceeds the amount of negative ions in the blower 100, the balance signal
252 into the microcontroller 201 will indicate this ion imbalance. The
microcontroller 201 will lengthen the negative pulse width (duration) 811
of negative pulses 804. Since the width 811 is lengthened, the amplitude
of the negative micropulses 802 is increased. The positive micropulses
801 and negative micropulses 802 are high voltages output that are driven
to the emitter points 102. The increased amplitude of the negative
micropulses 802 will increase the negative ions generated from the
emitter points 102. The ionization waveform 814 has generated variable
polarity groups of short duration ionizing micro-pulses 801 and 802. The
micro-pulses 801 and 802 are predominantly asymmetric in amplitude and
duration of both polarity voltages and have a magnitude of at least one
polarity ionizing pulses exceed the corona threshold.

[0060] Once the maximum pulse width has been reached for the negative
pulse width 811, if the amount of positive ions is still exceeding the
amount of negative ions in the blower 100, then the microcontroller 201
will shorten the positive pulse width (duration) 810 of positive pulses
803. Since the width 810 is shortened, the amplitude of the positive
micropulses 801 is decreased. The decreased amplitude of the positive
micropulses 801 will decrease the positive ions generated from the
emitter points 102.

[0061] Alternatively or additionally, if the amount of positive ions
exceeds the amount of negative ions in the blower 100, the
microcontroller 201 will lengthen the time between negative pulses 804 by
lengthening the negative Rep-Rate 813 (time interval between negative
pulses 804). Since the negative Rep-Rate 813 is lengthened, the time
between negative micropulses 802 is also increased. As a result, the
lengthened or longer negative Rep-Rate 813 will increase the time between
the negative micropulses 802 which will, in turn, increase the amount of
time negative ions are generated from the emitter points 102.

[0062] Once the minimum negative Rep-Rate has been reached for the
negative Rep-Rate, if the amount of positive ions is still exceeding the
amount of negative ions in the blower 100, then the microcontroller 201
will shorten the time between positive pulses 803 by shortening the
positive Rep-Rate 812 (time interval between positive pulses 803). Since
the positive Rep-Rate 812 is shortened, the time between positive
micropulses 801 is also decreased. As a result, the shortened or shorter
positive Rep-Rate 811 will decrease the time between the positive
micropulses 803 which will, in turn, decrease the amount of time positive
ions generated from the emitter points 102.

[0063] Alternatively or additionally, if the amount of positive ions
exceeds the amount of negative ions in the blower 100, the
microcontroller 201 will increase the number of negative pulses 804 in
the negative pulse output 816. The microcontroller 201 has a negative
pulse counter that can be increased so as to increase the number of
negative pulses 804 in the negative pulse output 816. Since the number of
negative pulses 804 is increased, the negative pulse train is increased
in the negative pulse output 816, and this increases the number of
negative micropulses 802 in the HV output which is the ionization
waveform 814 that is applied to the emitter points 102.

[0064] Once the maximum amount of negative pulses has been added to the
negative pulse output 816, if the amount of positive ions is still
exceeding the amount of negative ions in the blower 100, then the
microcontroller 201 will decrease the number of positive pulses 803 in
the positive pulse output 815. The microcontroller 201 has a positive
pulse counter that can be decreased so as to decrease the number of
positive pulses 803 in the positive pulse output 815. Since the number of
positive pulses 803 is decreased, the positive pulse train in the
positive pulse output 815 is decreased and this decreases the number of
positive micropulses 801 in the HV output which is the ionization
waveform 814 that is applied to the emitter points 102.

[0065] The following example is directed to achieving an ion balance in
the blower 100 when the amount of negative ions exceeds the amount of
positive ions in the blower.

[0066] If the sensor 101 and/or sensor 204 detects an ion imbalance in the
ionizing blower 101 where the amount negative ions exceed the amount of
positive ions in the blower 101, the balance signal 252 into the
microcontroller 201 will indicate this ion imbalance. The microcontroller
201 will lengthen the positive pulse width 812 of positive pulses 803.
Since the width 810 is lengthened, the amplitude of the positive
micropulses 801 is increased. The increased amplitude of the positive
micropulses 801 will increase the positive ions generated from the
emitter points 102.

[0067] Once the maximum pulse width has been reached for the positive
pulse width 812, if the amount of negative ions is still exceeding the
amount of positive ions in the blower 100, then the microcontroller 201
will shorten the negative pulse width 811 of negative pulses 804. Since
the width 811 is shortened, the amplitude of the negative micropulses 802
is decreased. The decreased amplitude of the negative micropulses 802
will decrease the negative ions generated from the emitter points 102.

[0068] Alternatively or additionally, if the amount of negative ions
exceeds the amount of positive ions in the blower 100, the
microcontroller 201 will lengthen the time between positive pulses 803 by
lengthening the positive Rep-Rate 812. Since the positive Rep-Rate 812 is
lengthened, the time between positive micropulses 801 is also increased.
As a result, the lengthened or longer positive Rep-Rate 812 will increase
the time between the positive micropulses 801 which will, in turn,
increase the amount of time the positive ions generated from the emitter
points 102.

[0069] Once the minimum positive Rep-Rate has been reached for the
positive Rep-Rate 812, if the amount of negative ions are still exceeding
the amount of positive ions in the blower 100, then the microcontroller
201 will lengthen the time between negative pulses 804 by lengthening the
negative Rep-Rate 813. Since the negative Rep-Rate 813 is lengthened, the
time between negative micropulses 802 is also increased. As a result, the
lengthened or longer negative Rep-Rate 813 will increase the time between
the negative micropulses 802 which will, in turn, decrease the amount of
time the negative ions generated from the emitter points 102.

[0070] Alternatively or additionally, if the amount of negative ions
exceeds the amount of positive ions in the blower 100, the
microcontroller 201 will increase the number of positive pulses 803 in
the positive pulse output 815. The microcontroller 201 has a positive
pulse counter that can be increased so as to increase the number of
positive pulses 803 in the positive pulse output 815. Since the number of
positive pulses 803 is increased, the positive pulse train in the
positive pulse output 815 is lengthened and the number of positive
micropulses 801 is increased in the HV output which is the ionization
waveform 814 that is applied to the emitter points 102.

[0071] Once the maximum amount of positive pulses has been added to the
positive pulse output 815, if the amount of negative ions is still
exceeding the amount of positive ions in the blower 100, then the
microcontroller 201 will decrease the number of negative pulses 804 in
the negative pulse output 816. The microcontroller 201 has a negative
pulse counter that can be decreased so as to decrease the number of
negative pulses 804 in the negative pulse output 816. Since the number of
negative pulses 804 is decreased, the negative pulse train is shortened
in the negative pulse output 816 and the number of negative micropulses
802 is decreased in the HV output which is the ionization waveform 814
that is applied to the emitter points 102.

[0072] If the ion imbalance (which is reflected in the balance current
value 252) is not significantly different from the setpoint 253, then a
small adjustment in the ion imbalance may be sufficient and the
microcontroller 201 can adjust the pulse widths 811 and/or 810 to achieve
ion balance.

[0073] If the ion imbalance (which is reflected in the balance current
value 252) is moderately different from the setpoint 253, then a moderate
adjustment in the ion imbalance may be sufficient and the microcontroller
201 can adjust the Rep-Rates 813 and 812 to achieve ion balance.

[0074] If the ion imbalance (which is reflected in the balance current
value 252) is significantly different from the setpoint 253, then a large
adjustment in the ion imbalance may be sufficient and the microcontroller
201 can add positive and/or negative pulses in the outputs 815 and 816,
respectively.

[0075] In yet another embodiment of the invention, a duration (pulse
width) of at least one polarity of the micro-pulses in FIG. 8 are at
least approximately 100 times shorter than a time interval between micro
pulses.

[0076] In yet another embodiment of the invention, the micro-pulses in
FIG. 8 are arranged in following one another groups/pulse trains and
wherein one polarity pulse train comprises between approximately 2 and 16
positive ionizing pulses, and a negative pulse train comprising between
approximately 2 and 16 positive ionizing pulses, with time interval
between the positive and negative pulse trains that is equal to
approximately 2 times the period of consecutive pulses.

[0077] The flowchart in FIG. 3 shows feedback algorithm 300 of the system
200, in accordance with an embodiment of the invention. The function of
providing ion balance control by use of the feedback algorithm 300 runs
at the end of an ionization cycle. This algorithm is performed by, for
example, the system 200 in FIG. 2. In block 301, the balance control
feedback algorithm is started.

[0078] In blocks 302, 303, 304, and 305, the calculation of the control
value of the negative pulse width is performed. In block 302, an error
value (Error) is calculated by subtracting the desired ion balance
(SetPoint) from the measured ion balance (BalanceMeasurement). In block
303 the error value is multiplied by the loop gain. In block 304, the
calculation of the control value is limited to minimum or maximum values
so that the control value is limited and will not be out of range. In
block 305, the control value is added to the last negative pulse width
value.

[0079] In blocks 306, 307, 308, and 309, the pulse width is incremented or
decremented. In block 306, the negative pulse width is compared with a
maximum value (MAX). If the negative pulse width is equal to MAX, then in
block 307, the positive pulse width is decremented and the algorithm 300
proceeds to block 310. If the negative pulse width is not equal to MAX,
then the algorithm 300 proceeds to block 308.

[0080] In block 308, the negative pulse width is compared with a minimum
value (MIN). If the negative pulse width is equal to MIN, then in block
309, the positive pulse width is decremented and the algorithm 300
proceeds to block 310. If the negative pulse width is not equal to MIN,
then the algorithm 300 proceeds to block 310. When the negative pulse
width hits its control limit, a change in the Positive pulse width will
shift the balance in such a way as to over shoot the balance setpoint,
forcing the Negative pulse to its limit.

[0081] In blocks 310, 311, 312, and 313, the pulse repetition rates
(Rep-Rates) are incremented or decremented when pulse width limits are
met. In block 310, the positive pulse width is compared with MAX and the
negative pulse width is compared with MIN. If the positive pulse width is
equal to MAX and the negative pulse width is equal to MIN, then in block
311, alternately, the positive pulse repetition rate (Rep-Rate) is
incremented OR the negative pulse Rep-rate is decremented. The algorithm
300 proceeds to block 314. If the positive pulse width is not equal to
MAX and the negative pulse width is not equal to MIN, then the algorithm
300 proceeds to block 312.

[0082] In block 312, the positive pulse width is compared with MIN and the
negative pulse width is compared with MAX. If the positive pulse width is
equal to MIN and the negative pulse width is equal to MAX, then in block
313, alternately, the positive pulse repetition rate (Rep-Rate) is
decremented OR the negative pulse Rep-rate is incremented. The algorithm
300 proceeds to block 314. If the positive pulse width is not equal to
MIN and the negative pulse width is not equal to MAX, then the algorithm
300 proceeds to block 314.

[0083] The Positive and Negative Pulse width control is used when the
balance is close to the setpoint. As the emitter points age or as the
environment dictates, the Positive and Negative Pulse width control will
not have the range and will "Hit" is control limit (Positive at its
Maximum and Negative at its Minimum (or vice versa)). When this happens
the algorithm changes the Positive or Negative Rep-Rate, effectively
increasing or decreasing the amount of On-Time of the Positive or
Negative ion generation and shifts the balance toward the setpoint.

[0084] In blocks 314, 315, 316, and 317, the pulse repetition rates
(Rep-Rates) are incremented or decremented when pulse width limits are
met. In block 314, the positive pulse Rep-Rate is compared with a minimum
pulse repetition rate value (MIN-Rep-Rate) and the negative pulse
Rep-Rate is compared with a maximum pulse repetition rate value
(MAX-Rep-Rate). If the positive pulse Rep-Rate is equal to MIN-Rep-Rate
AND the negative pulse Rep-Rate is equal to MAX-Rep-Rate, then in block
315, one negative pulse is shifted to a positive pulse through an offtime
count, and the algorithm 300 then proceeds to block 318 during which the
balance control feedback algorithm 300 ends. An offtime count is when the
ionization waveform is off. The off-time is the time between negative and
positive and positive and negative group (or train of pulses) of pulses
and is defined here as a count, equal to a pulse duration with a Positive
or Negative Rep-Rate.

[0085] If the positive pulse Rep-Rate is not equal to MIN-Rep-Rate AND the
negative pulse Rep-Rate is not equal to MAX-Rep-Rate, then the algorithm
300 proceeds to block 316.

[0086] In block 316, the positive pulse Rep-Rate is compared with
MAX-Rep-Rate and the negative pulse Rep-Rate is compared with
MIN-Rep-Rate). If the positive pulse Rep-Rate is equal to MAX-Rep-Rate
AND the negative pulse Rep-Rate is equal to MIN-Rep-Rate, then in block
317, one positive pulse is shifted to a negative pulse through an offtime
count, and the algorithm 300 then proceeds to block 318 during which the
balance control feedback algorithm 300 ends. If the positive pulse
Rep-Rate is not equal to MAX-Rep-Rate AND the negative pulse Rep-Rate is
not equal to MIN-Rep-Rate, then the algorithm 300 proceeds to block 318
during which the algorithm 300 ends.

[0087] When the Rep-Rate control hits the limit, the algorithm triggers
the next adjustment control level.

[0088] Shifting a micro pulse from Positive pulse group to Off-Time pulse
group to Negative pulse group, shifts the balance in the Negative
direction. Conversely, shifting a micro pulse from Negative pulse group
to Off-Time pulse group to Positive pulse group, shifts the balance in
the positive direction. Using the Off-Time group reduces the effect, and
thus provides a finer control.

[0089] A flowchart in FIG. 4 shows an algorithm 400 of a micropulse
generator control. Waveforms of driving pulses and a high voltage output
illustrated in the diagram of FIG. 8. This algorithm 400 is performed by,
for example, the system 200 in FIG. 2. In block 401, an interrupt service
routine of Timer1 is started. The algorithm 400 for the micropulse
generator runs, for example, every 0.1 milliseconds.

[0090] In block 402, a micropulse repetition rate counter is decremented.
This counter is the repetition rate divider counter of Timer1. Timer1 is
the main loop timer and pulse control timer running at 0.1 ms. Timer1
turns on the HVPS output, thus the start of the micro pulse, where Timer0
turns off the HVPS, ending the micro pulse. Therefore, Timer1 sets the
rep-rate and triggers the Analog to digital conversion, Timer0 set the
micro pulse width.

[0091] In block 403, a comparison is performed if the micropulse
repetition rate counter is equal to 2. In other words, a test is
performed to determine if the Rep-Rate divider count is 2 count from the
start of the next micropulse. The step in block 403 will synchronize the
ADC (in the microcontroller 201) to a time just before the next
micropulse transmission. If the micropulse repetition rate counter is
equal to 2, then the sample and hold circuit 205 is set to sample mode as
shown in block 404. In block 405, the ADC in the microcontroller 201
reads the sensor input signal from the sample and hold circuit 205.

[0092] If the micropulse repetition rate counter is not equal to 2, then
the algorithm 400 proceeds to block 406.

[0093] Blocks 404 and 405 starts and performs the Analog-to-Digital
conversion to permit the microcontroller 201 to measure the analog input
received from the sample and hold circuit 205.

[0094] When the sample and hold circuit 205 is enabled, typically at
approximately 0.2 milliseconds before the next micro-pulse occurs at
block 403 with the micropulses 803 and 804 having pulse widths 810 and
811, respectively, the signal 250 (FIG. 2) is then conditioned by the low
pass filter 206 and amplified by amplifier 207 before being applied to
the input of the Analog to Digital Converter (ADC) residing inside the
Microcontroller 201. Just after the sample and hold circuit 205 is
enabling (block 404) a sample and hold operation, the ADC is signaled to
start a conversion (block 405). The resulting sample rate of the balance
signal is typically about 1.0 millisecond, and in synchronization with
the micropulse repetition rates (rep-rate). However, the actual sample
rate varies as rep-rate 812, 813 (FIG. 8) varies (as shown in blocks 310,
311, 312, 313) but will always remain in synchronization with the
micropulse rep-rate 812, 813.

[0095] According to this embodiment, the method of signal sampling before
the next micropulse allows the system 200 to ignore noise and current
surges (capacitive coupled) and advantageously avoid corrupting the ion
balance measurement.

[0096] In block 406, a test is performed to determine if the Rep-Rate
divider counter of Timer1 s ready to begin the next micropulse. A
comparison is performed if the micropulse repetition rate counter is
equal to zero. If the micropulse repetition rate counter is not equal to
zero, then the algorithm 400 proceeds to block 412. If the micropulse
repetition rate counter is equal to zero, then the algorithm 400 proceeds
to block 417.

[0097] In block 417, the micropulse repetition rate counter is reloaded
from data registers. This will reload the time interval for the start of
the next pulse (micropulse). The algorithm 400 then proceeds to block
408.

[0098] Blocks 408, 409, and 410 provide steps that determine if a new
Pulse Phase is started or to continue the current Pulse Phase.

[0099] In block 408, a comparison is performed if the micropulse counter
is equal to zero (0).

[0100] If so, then the algorithm 400 proceeds to block 410 which calls the
next pulse phase, and the algorithm 400 proceeds to block 411.

[0101] If not, then the algorithm 400 proceeds to block 409 which calls to
continue the present pulse phase.

[0102] In block 411, the Timer0 (micropulse width counter) is started. The
Timer0 controls the micropulse width, as discussed below with reference
to blocks 414-417.

[0103] In block 412, all system interrupts are enabled. In block 413, the
interrupt service routine of Timer1 is ended.

[0104] When the Timer0 time expires, the actual micropulse width is
controlled based on blocks 414-417. In block 414, the interrupt service
routine of Timer0 is started. In block 415, the positive micropulse drive
is set to off (i.e., the positive micropulses are turned off). In block
416, the negative micropulse drive is set to off (i.e., the negative
micropulses are turned off). In block 417, the interrupt service routine
of Timer0 is ended.

[0105] As also shown in portion 450 in FIG. 400, for a micropulse drive
signal 452, the duration of Timer0 is equal to the micropulse width 454
of micropulse drive signal 452. The micropulse width 454 begins at pulse
rising edge 456 (which is triggered at the start of the Timer0) and ends
at the pulse falling edge 458 which is triggered at the end of the
Timer0).

[0106] Details of a method 700 of averaging the ion balance sensor input
are shown in flowchart in FIG. 7. Blocks 701-706 describes the operations
of the sample and hold circuit 205 and ADC conversion of data from the
sample and hold circuit 205. At the end of the ADC conversion 701, about
0.1 milliseconds later, the sample and hold block 205 is disabled,
preventing the noise and current surges from corrupting the balance
measurement. The resulting measurement 703 and Sample Counter 705 are
added to the previous Raw Measurement Sum 704 value and saved, waiting
further processing. Blocks 707-716 is an averaging routine for averaging
the measurements of the sensors 101 and/or 204 and obtains an Ion Balance
Measurement Average that is then combined using a Finite Impulse Response
calculation to combine the Balance Measurement Average with previous
measurements 714 yielding the a final Balance Measurement used in the
balance control loop. The calculation in block 714 calculates a weighted
average from a previous series of sensor input measurements. In block
715, an event routine is called to make an adjustment on the ion
generation based on the calculation in block 714.

[0107] The flowcharts in FIGS. 5A, 5B, and FIG. 6 illustrate system
operation during formation of negative and positive polarity pulse
trains. An Ionization cycle 531 is comprised of a series of positive
pulses 502, 602, followed by an off time interval 503, 603, followed by a
series of negative pulses 517, 604 followed by an off time interval 518,
605. When the specified number of Ionization cycles has occurred 708, the
Ion Balance Measurement Average is calculated 709, and the Raw
Measurement Sum 710 and Sample Counter values are cleared 710, 711.

[0108] Reference is now made to FIGS. 5A, 5B, and 6. These figures are
flowcharts of a system operation during the formation of a negative pulse
train and a positive pulse train, respectively in accordance with an
embodiment of the invention. In block 501, the routine of the next pulse
phase for a negative pulse train is started. Blocks 502-515 describe the
steps for generating negative series of pulses and the off time of the
pulse duration. Blocks 517-532 describe the steps for generating positive
series of pulses and the off time of the pulse duration. Blocks 601-613
describe the steps for generating the next pulse phase or if the present
pulse phase continues.

[0109] The Balance Measurement Average is then combined using a Finite
Impulse Response calculation to combine the Balance Measurement Average
with previous measurements 714 yielding the a final Balance Measurement
used in the balance control loop.

[0110] The balance control loop 301 compares the Balance Measurement to
the set point value 302 yielding an error value. The Error signal is
multiplied by the loop gain 303, checked for over/under range 304 and
added to the present Negative Pulse Width value.

[0111] In the micropulse HV supply system 202, 203, the pulse width of the
driving micropulse, changes the peak amplitude of the resulting High
Voltage (HV) wave 814, 801, 802. In this case the negative pulse
amplitude is change to effect a change in the Ion Balance. If the error
signal value is greater than zero, the Negative pulse width is adjusted
up, thus increasing the negative HV pulse amplitude as a result, changing
the balance in the negative direction. Conversely, if the balance is
negative, the Negative pulse width is adjusted down, thus changing the
balance in the positive direction.

[0112] During continual adjustments of the Negative pulse width and as
conditions warrant, the Negative pulse width may hit its control limit.
In this situation the Positive pulse width is adjusted down 307 for a
positive out-of-balance or up 309 for a negative out-of-balance until the
Negative pulse width can again resume control. This method of control
using the Negative and Positive pulse width yields an average balance
control adjustment range of approximately 10V with a stability of less
than 3V.

[0113] According to another embodiment under large out-of-balance
conditions, for instance at the Ionizing blower start up, significant
contamination builds up or erosion of the emitter(s) as the they ages,
the Negative pulse width and the Positive pulse width will reach their
control limits 310, 312. In this situation, the Positive pulse repetition
rate and the Negative pulse repetition rate are adjusted 311, 313 to
bring the balance to the point where the Positive pulse width and
Negative pulse width are once again in their respective control ranges.
Therefore, for a large positive out-of-balance condition the Negative
pulse repetition rate is increased 313, resulting in a negative shift in
balance. If the condition still exists, the Positive pulse repetition
rate is decreased 313, also resulting in a negative shift in balance.
This alternating method of changing the Positive/Negative rep-rate 313
continues until the Negative pulse width and the Positive pulse width are
once again within their control ranges. Likewise, for a for a large
negative out-of-balance condition the Positive pulse repetition rate is
increase 311 alternately the Negative pulse repetition rate is decreased
311 resulting in a positive shift in balance. This continues, as before,
until the Negative pulse width and the Positive pulse width are once
again within their control ranges.

[0114] In the case where an extreme out-of-balance condition exists, the
both the Negative/Positive pulse width and Positive/Negative rep-rates
adjustments may have hit their respective control limits 310,312 314,
316, the Positive pulse count and the Negative pulse count will then be
changed to bring the balance to a point where the Positive/Negative
rep-rates are once again within their respective control ranges.
Therefore, for an extreme positive out-of-balance condition the Positive
pulse count will decrease 317 and the Off-time Pulse Count 317 will be
increased by one pulse count, resulting in a negative change in balance.

[0115] If the condition is still exists, the Off-time Pulse count will be
decreased 317 and the Negative pulse count will increase 317 by one pulse
count, resulting in a further negative change in balance. This shifting
of one pulse from negative to positive packets/trains continues until the
Positive/Negative rep-rate is once again within their control ranges.
Likewise, for a for an extreme negative out-of-balance condition one
pulse at a time will be shift from the positive pulse 315 packet/train
through the off-time pulse count to the negative pulse packet 315
resulting in a positive change in balance until the Positive/Negative
rep-rate are once again within their control ranges.

[0116] In a parallel process, the Balance Measurement is compared to the
setpoint. If the Balance Measurement is determine to be outside its
specified range, corresponding to an average CPM (Charge plate monitor)
reading of +/-15V measured at 1 foot from the ionizer, the control system
of the Ionizer will trigger a balance alarm.

[0117] In FIG. 9 is method for providing a feedback routine that actuates
an ion balance alarm if an ion imbalance is present. Blocks 901-909
performs measurements that are compared with threshold values to
determine if a balance alarm is actuated. Blocks 910-916 determines if a
balance alarm is actuated

[0118] In a timed interval of once every 5 second, the Balance Measurement
is evaluated 903, when outside this range a "1" is left shifted into the
Alarm register 904 otherwise a "0" left shifted into the Alarm register
902. When the Alarm register contains a value of 255 (all "1"s) the
Balance Measurement is declared in alarm. Likewise if the Alarm register
contains a value of 0 (all "0"s) the Balance Measurement is declared not
in alarm. Any value of the Alarm register not 255 or 0 is ignored and the
state of the alarm is unchanged. This filters the Alarm notification and
prevents sporadic notifications. As a byproduct, the notification delay
allows sufficient time for the Balance control system to recover from
external stimulus.

[0119] In another parallel process running at the end of each ADC
conversion cycle, about every 1 milli-second FIG. 9B, the balance control
system is monitored. This routine 910 checks the Positive and Negative
pulse counts for limit condition 911, 912. As stated above, when an
out-of-balance condition exists and the Positive/Negative pulse width and
the Positive/Negative rep-rate are at their respective limits, the
Positive and Negative pulse counts are adjusted. However in the event the
Balance cannot be brought back into the specification the and the
Positive/Negative pulse counts have reached their adjustment limit 911
912, an alarm state is force by setting the Alarm register to a value of
all "1"s 913, setting the Alarm flag 914, and setting both alarm status
bits 915.

[0120] The method and technic of automatic balance control discussed above
is not limited to one type of ionizing blower. They can be used in
different models of ionizing blowers with variety emitter electrodes.
Other applications of the automatic system include models of ionizing
bars with micro-pulse high voltage power supplies.

[0121] The above description of illustrated embodiments of the invention,
including what is described in the Abstract, is not intended to be
exhaustive or to limit the invention to the precise forms disclosed.
While specific embodiments of, and examples for, the invention are
described herein for illustrative purposes, various equivalent
modifications are possible within the scope of the invention, as those
skilled in the relevant art will recognize.

[0122] These modifications can be made to the invention in light of the
above detailed description. The terms used in the following claims should
not be construed to limit the invention to the specific embodiments
disclosed in the specification and the claims. Rather, the scope of the
invention is to be determined entirely by the following claims, which are
to be construed in accordance with established doctrines of claim
interpretation.